When its all said and done I don't think the SBC will be that much cheaper to have everything working like OEM. Then yes that much power will probably show its ugly head somewhere downstream of the flywheel costing you more.
I guess it comes down to how much power do you want/need? 3.4 is pretty stout. The SC would not be cheap but would give you mild SBC power if wanted later.
Speski OffRoad LTD, Cargo Solutions for Toyota 4x4's http://www.SpeskiOffRoad.com
"80 series, with a fridge"
1976 FJ40, Project with little progress.
2004 Starcraft 10RT