Alteredspeed

New to the MJ but have built many XJ’s. I picked up a ‘88 Pioneer. Really good rust free shape. Plans are Iron man 4 link front and rear. Coilovers front and rear on 40’s. I really want to go diesel and have researched TDIs but I’m afraid I’ll be disappointed with the power? Really want a hemi but don’t want to chop up the firewall. So LS? Or TDI any input from people who have done it?