55-59 Engine Placement Question - V8 Swap

[Strider]

Hi,

Currently building a 57 GMC truck and having issues with engine placement in terms of the distributor hitting the firewall and potential for the TH350 not going to fit. Pics show issues.

I put in a sbc in the truck using a Trans Dapt motor mount kit. I based the placement of the engine. To determine placement, I bolted a cast bellhousing to the back of the engine, then bolted that down to the stock bellhousing crossmember ( as I was going to use a 5 speed before). Then I leveled the engine intake and bolted the Trans Dapt motor mounts to the frame. Engine fan is sitting 5 inches from rad. Large HEI GM distributor touches firewall with cab bolted back down. TH350 trans that I am now going to use seems that it will be a tight fit under the floor. Pics show this. Trans needs to come up another 2 inches and go forward another 1 inch or so.

Question is, did I make a mistake basing the placement of the engine off the bellhousing crossmember (which is now removed so that the auto trans can go in)?
What distributor should I use?


Trans Dapt mounts



firewall / trans pic





Any thoughts or help would be sincerely appreciated. My "expertise" is 67-72 trucks. I'm still learning on the TF ones!

Cheers! Enjoy your build.