Which HP motor should I put on which tractor?

I have 1 Briggs Vanguard 18hp with I'm guessing less than 500 hours and 1 Briggs Vanguard 16hp with I'm guessing 600 hours on it. I mow lawns part time and the Toro 117 will be the primary machine. The Case 448 I got after the original motor was removed so it will be a project to put it back together correctly but I plan to use an electric clutch in it instead of the troublesome mechanical unit.
Thoughts, ideas?

I have had problems with the Vanguard cracking the block,because of the mounting to the frame. Still haven't solved the issue yet. Am trying to get in touch with Ingersoll now to resolve the issue.

Good Luck

I picked up a Deere 330 garden tractor without the Yanmar Diesel engine. I wanted something hydrostat to put my Brantley loader on. And I had a good running M18 Kohler Twin. So you would think everything is straight forward: drop the M18 on it, attach the loader, and go.

Well I recently picked up a free Bolens 1900 Eliminator that does not have an engine. It has the 2-speed rear end, a hydro transmission, and best of all- it is foot controlled (unlike the Deere), which I would need 3 hands to operated with the loader. But the input shaft on the Bolens hydro pump is wobbley and leaks. So now some plans may have to be changed. And to top it off, I just found an almost complete Yanmar Diesel (from a 330) engine for sale.

What do I do.. I would rather have the loader on the BOlens so that it is easier to operated, and it has better stability.

Oh yeah! I would put the 18hp on your Toro.
Good Luck with your decisions!!