Can I reuse the stock cross member/mount/TA bracket if I am using a 7004r with my 5.3 swap?

Yes as long engine mounted and same spot would use sbc lsx style mounts

I was planning on using the Hawks mounts that allow me to use the stock clam shell on the motor

Here's what I have for a parts list so far, aside from the wiring and fuel what should I add to bolt a 5.3 out of a truck in this car? I am picking up an fbody accessory drive and a ls1 intake with fuel rails and injectors this weekend.

Crank Spacer for 700r4 - GM parts Direct -pn 12563532 - $25
Convertor Bolts - Gm Parts Direct - pn 12563533 - $5
TV cable/bracket - BowTieOVerDrives.com - Part #: TVEZLS1BR - 169.95
Motor Mounts - Hawks - PN sp-971 - 89.99

You need Fbody clamshells off a 98-02 LS1 to use the hawk mounts. For a budget 5.3 conversions assuming you're starting with a V8 car... Use the SBC adapter plates with a 1" setback. There are diagrams found via google for a DIY job

Yes we have a 85 z28. I went ahead and got the hawks, I heard with the plates I wouldnt have enough room to notch the K member for the 4th gen AC compressor. I have those, the 99 corvette fuel filter with regulator in it, and found a deal on a 5.3 that was in a trans am wrecked, getting the whole motor with accessory drive, f body harness, pcm, and 4l60e for a smoking deal on Sunday. Just have to figure out what Im gonna have to do to adapt the stock fuel lines to the regulator and the ls1 fuel rails, have a few buddies that have done several ls swaps so hopefully they will help with wiring, and I should be set to go!

Im going to start a new thread since this one has a misleading title to the questions at hand now that I am going with a different transmission and I cannot edit it. If a mod could delete that would be great

Older post here, do you know if the Spohn motor mounts using 4th gen clamshells will allow me to use the factory transmission cross member?