Bohemian

So this is the cliff notes version of How to R&R 3rd Gen Motor Mounts “Without A Coil Spring Compressor” or dropping the a-frames all or in part.

My Vehicle is a 89 Camaro RS Convertible rolling stock with a SBC.

So in my scenario I was working in the street in front of my house, with the following tools:
1. a single floor-jack.
2. (2) jack-stands.
3. (4) tire chocks.
4. a creeper.
5. a corded led work light that sits on the ground and can be pointed straight up.
6. (1) 12” 3/8” drive extension.
7. (1) 3/8” drive 6-point 15mm swivel/universal/flex socket.
8. (1) 3/8” drive ratchet.
9. (1) 15mm combination wrench
10. PB Blaster

You might be able to use air tools, but I did not given the fact everything is so fricken tight & cramped that I felt it'd be easier with hand tools. I also did this in it's entirety by myself.

My nuts & bolts on my motor-mounts were both 15mm yours might be a different size, check before you round off your nut's and bolts and have to cut them off with a torch or cut-off wheel!

Steps:
1. Jack-up front of car & place on two jack-stands placed on the common uni-body pseudo frame rail standard jack points around the front of the doors, near the tranny tunnel. You need the front end unloaded so you can get to the motor-mount bolts on the k-member without dropping the a-frames all or in part & using a coil spring compressor etc.
2. Block/Chock your rear wheels, on each side of tire (front & back). 4 Chocks total you don't want that car rolling off the jack-stands while you're under it! The chocks I used are some heavy rubber ones from harbor freight that are cheap $ that I've used for years without issue; one of the few things from harbor freight that have lasted for me.
3. Use the attached pictures for reference of placement of 12” extension & 15mm flex socket for the 3 motor-mount bolts that go through the k-member. This is the key to not needing to use a coil spring compressor and dropping the a-frames all or in part solely to r&r the motor-mounts.
4. I was able to easily put a 15mm combination wrench on the top side & use the ratchet to unscrew the nuts. The led work-light pointed straight up at the nuts made it easy for me to see the 3 nuts to remove well-enough to get the 15mm flex socket on them. My car is a California car so no rust issues under car, but I PB Blaster'd the nuts & bolts before I started unscrewing anything & let it sit for 15 minutes or so before I got after it. IF yours are rusted maybe PB Blast them a few times over the course of a few days before making this a weekend project & you'll usually be good to go.
5. Installation is the reverse of removal with the exception that I brake cleaned the nuts & washers and super-glued the washers to the nuts due to the fact that with the a-frame still in place you're the underdog to get those washers to stay in place long enough to get the nuts started. Couple pictures show the super-glued washers to the nuts.

Note: My engine was/is out of car at the time this was done; it will still work with your engine in car; but you need to use a floor jack & 2x4's to jack up engine high enough to get mounts in & out. I've previously done this with a 2x4 under oil pan or harmonic balancer, while I was working I stacked enough 2x4's under engine that I did not have to depend on floor-jack to hold engine up while I was working under it. Never, Ever trust your life to a floor-jack, bottle jack or scissors jack etc, spend the money on the best jack stands you can afford.

Superglued nut & washer.

12" 3/8 Drive Extension with 15mm flex socket.

Bottom most nut & bolt.

Top, Rear most nut & bolt.

Top, Front most nut & bolt.