1975 SeaCraft CC , 18' ..Transom height change ??

[striker]

Hi there all , first post here . Nephew has recently aquired an 18' CC and we are taking it apart ... of course he is doing most of the get started (dirty grunt) work , I got my own Montouk B.W. going on right now (or I should say waiting for me to start up on it again , I'm lazy , it's my 8th boat) .

His boat - Gunnel and deck cap is off , T-top is off , rub rails off , interior shell is out (has locker each side of trans.) , tank is out . He is working on seperating the existing ply from the glass transom (in progress , no problems yet) .

I want to raise the transom height 5" when we do the rebuild . It is 20" from top to bottom as it is now . (for clarity because I may not always use correct terms to identify things , I'll elaborate like this , "that is from where the motor bracket would seat down full tight - to the very bottom of the V (keel) in the center") . Again that measurement is 20" .

When rebuilt I would like it to be 25" if that will work ?? I haven't any problem with the rebuild part of it (yet) , but would like to know we have some friends here for future as this project goes along .

So my question is ... if I rebuild from existing 20" , to desired 25" , what shaft length should the "New" motor be ( he thinks he will get a 150 hp) ?? Would a 25" transom require a 30" shaft motor , and if so , will that work OK on his boat ??

Is there anything unusual about a 30" shaft motor that we should think about (compared to other outboards) ??

Can he purchase (New) a 30" shaft motor just as easily as a 25" shaft ??

Ah , I think I'm picking up 2 sheets of 3/4" Okume on Mon. to get ready . I'll be giving him a list of epoxy and fabric supplys to get soon .

thanks in advance ... will be checking back soon , Dan

ps., ... it's not that I can't go talk with the marina guys , it's more like I'd rather start here ... it's his boat , I'm just the ol Uncle , lol .

pss., ... no , do not want a seadrive bracket