Car engine flywheel spacer any experience?

I'm in the beginning stages of a car project, and i'm doubting, should i keep the insufition factory petrol engine, or do a diesel swap, the only complication is there are no factory bolt on gearboxes for those engines, so people are making adapters to fit them but also a flywheel spacer is needed, and i've never had to make one before, so i wanted to ask has anyone made one, what to look for , what material to make it from, also can i make strong enough bolts, because factory one are way too short, this is a picture i found of someone had made exacly for aplication like i need.
I would buy proper 12.9 grade bolts or better to attach the flywheel. It might be possible to find some special alloy bolts that are stronger than 12.9. The spacer could be made from 4150, 8620, or 4340. The spacer would have to pin very tightly to the crankshaft and flywheel to keep it from trying to rotate. Everything will have to be a tight fit.

The last time I did this, about 40 years ago, I shortened the bell housing rather than spacing the flywheel. That moved the gearbox closer to the engine.
Ahh, I see the problem. So yes, spacing the flywheel would be the best option. On one engine swap I just cut out the firewall and moved the engine back about 100mm. But I used to do some crazy stuff :grin: I'm older and wiser now :)
I'm trying to keep it as stock as possible, but that never go as planned, also needs to pass inspection and using a different manufacturer engine is already one red flag.
I’ve seen flywheels wind up in the dashboard up by wind shield when they fly off.scatter shield for sure.

Yeah it's happened to me too. Had a pressure plate exploded, destroyed the car almost decapitated me. This been a low revving diesel application with only 63 HP bubble gum would probably hold but i'll overengineer it to be safe.