I am new to installing headers and have attached a set of Headman shorties to my 305. Thought I had the collector bolts tightened up enough on the driver side but when I checked on it the other day found that I lost one nut, the one on the inside closest to the motor.
The position of this bolt is nearly impossible to get a tool on it. Can't get a socket on the top as it's too thick to fit between the nut and the pipe from the top and from the bottom you can barely get your hand in there.
Looking for any tips on getting that tightened up without starring at it for hours and swearing!

 

Dent the tube until you can fit what you need on there. There exist specialty access tools for these scenarios as well.

 

^^^^This.

"Bolt-on" aftermarket stuff rarely does without some modification. As above, 'clearance' the area so you can get a socket on the nut.

 

Yup, unfortunately header installation typically includes the use of a hammer

I've found ratcheting wrenches are also helpful in these situations.

When you get them tightened down, drive it a few times to get a solid warm-up/cool-down cycle, then check them again.