Restoring an 80 Z28. Big kinda out there plans with this one. So far though budgets limited and just want to make this a solid car. Plenty of rust in this bucket got my work cut out for me. Updating the whole car, any ideas on mods I should consider while I have this torn apart?

 

So am I understanding that your plan is to extend from the front subframe to build a complete frame to the rear? Sounds like a lot to tackle, and would be tough to do if you don't have a frame jig to build from. It can be done on a level concrete floor, but it wont be easy to get things square and perfect.
There really isn't a "subframe" in the rear to join to the front. It's unibody back there, and you can get subframe connectors to hook the unibody rear to the subframe in front.

 

Looking for options as far as replacing the stock metal fuel tank with a plastic tank and skid. So far doesnt seem to be anything online as far as one specific for this model. Thinking goin with something similar and mod the trunk unless someone can point me in a better direction.

 

There are no "kits" for this. Its all a fab your own deal. Honestly if you didnt know that you may be in over your head. The later cars are a pain because of the hump for the larger fuel tank. This started in '74ish before that the trunk was flat. Ours have a giant hump and it is tricky to get a cell to sit level. It sucks trying to bolt one in the trunk and it also sucks trying to cut the trunk pan out. You have to built spacers for one side to keep it level. I gave up and used a stock tank because it wasnt going to look good any way I did it to me.

 

Ya why they put that hump in the design...perhaps tryin to strengthen that section but it seems pretty impractical. I'll leave the tank in same location as stock, cut out that section that slopes and refab it flat. So far with all the rust Im finding already feelin a bit overwhelmed, as this is my first restore Im not going to get discouraged. I work at a machine and fab shop, metal isnt too outta my realm. Anything I should know tho bout these tanks? It looks like if i wanted to keep the filler neck the tank would need some modding to...