Nice dave maybe you can use a 10 or 15 as a pony engine to start it ( had to say that)
Just lucked out in the other direction (smaller) got an Irvine 20 diesel for $53 on flea bay, guy has a good rating used but stated to be in great shape said a few cosmetic scratchs on back plate (plastic) he fitted a spring under the tommy bar guess he lost the grub screw to lock it . I have a spare screw
so will use it and leave my NIB irvine 20 in the box for now and use this one martin

Dave I would drill and tap for pressure fitting if you do not need it just use a small cap screw to seal it off