'98 fleetmaster and Allison XTB 21

I've bought a mercury with a '98 fleetmaster (standard) lower unit. It does not have a nosecone or low water pickup. (1) Is anyone running a standard lower unit like this on their Allison and if so, how far below the pad is it being run to get good water pressure and what prop works well? (2) At what speed is blow-out a likely problem? (3) Also, if it is necessary to run a low water pickup/nose come lower unit, can I install a heavy duty bearing carrier/associated parts in this lower unit to beef it up enough to run high with surfacing props? As I understand it, the lower unit was changed in '98 and I don't know if they are good candidates to be "worked" on or not. It would probably be cheaper to "work" this lower unit than buy a sport/torque master and have the Allison changes done to it.
Your thoughts?

85 ish is where blow out will occur with a merc lower unit, unless you're there, nothing to worry about.

Have you posted this on the Allison forum? Those guys will take good care of you.

Yeah, they are having some issues with the site. Sent an email to the administrators...hopefully will be able to post soon.