Crazy how some people spend money alright but the Chevy conversion into these units is pretty slick! .
About 1980 I put an Nos Marine Chevy 302 into one of these Toyotas and the best part was the Toyota trans bolted up to the Chevy bellhousing! .
From what I remember, I swapped the front and rear driveshafts to set the engine/trans assy further forward a few inches for distrib. clearance, made a custom pilot bushing to fit the Toyota input shaft and added one of those Pinto flexible steering shafts to get around it all...think I put a Saginaw pwr. steering box in too? .
The Nos Marine 302's where available here in Peterboro' from Outboard Marine if you had the right OMC connection for a short period and I think the ticket was $500! . Managed to get a few and send them on their way in different vehicles....shoulda'-woulda'-coulda' grabbed extras or saved some but didn't!

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~ Pete