Nissan SD25

[Dieselnut59]

A customer of ours recently "traded in" a 5000# capacity Nissan forklift that the transmission has taken a dump in (due to lack of service in its 4200 hours). The engine has been well serviced serviced and cranks and runs GREAT. I am trying to decide if I should find a little Nissan truck (they were available up until the mid 80's with this same engine and the virtually identical SD22) or if I should rebuild the transmission on this forklift. Either way, I will have to pay our company $500 for it (what we have in the "trade in"). It would make a sweet little conversion. It is an all-iron, pushrod, gear driven 4 cylinder engine. I really don't "need" another vehicle, except to have a small fuel saver vehicle with a manual transmission. I could honestly have more use out of the forklift and could then get rid of my current LPG/Gasoline 3000# capacity lift. The transmission will probably cost around $2000 to rebuild RIGHT (fwd clutches are SHOT) and it is a ROYAL PITA to remove/install, one of the worst in the industry, although it IS a tough design.
We are in the forklift sales, service, parts and rentals business, so I have been around the industry nearly all my life. I have rebuilt a couple Nissan transmissions and we have excellent sources for parts for any brand of lift.
I was looking in the parts book and this engine was available in Japan with a turbocharger as well as manual or automatic transmission, which means I could get a manual transmission flywheel pretty easily if I decide to put it in a truck.
What's yall's opinion... Do I upgrade my forklift (most practical) or do I find a Nissan truck and do a diesel conversion (most challenging and "cool")?
Thanks, John