you flip the assembly over, and with gravity pulling the float to the top, you measure between the top and the float. instructions will have a picture and a dimension.
post pictures of the underside of the deck, the transom area from around the motor, the stringer grid.
1/2" floor should be more than adequate with a sound stringer system. I believe they are on 16" centers on the early 70's gibsons....unless the floor has had an improper repair/replacement in...
if the boat was in near perfect shape, all original, and rot free, at most $1500.
however because the motor has no parts support, and the probability of the transom, stringers and deck to be in need of replacement is well over the 95% mark, it has zero value.
if it was a long-lost family boat...
How...... Spend $2-3000 in parts and if you can't do the work yourself, an additional $2000 in labor.
However there is no improvement in power or fuel economy. And the parts go obsolete quickly
The Chris Craft company of today has nothing in common with the company of 1972. The name has been bought and sold many times since then, and the records didn't follow the name
test drill your stringers and transom. use a 5/16" drill, mark off 3/4" length. drill into the encapsulated wood of the stringers and the transom about 4" up from the bottom of the deck. if the wood shavings come out dry, light colored, and smell like fresh sawn wood, then you are good...
could be any of the composites out there like Nida core or eqivalent. bear in mind, its 4x the cost of marine ply
https://merrittsupply.com/product/nida-core-structural-honeycomb-plain-h8pp/
Lets look at it another way. its not really fun to have to fish the refrigerator out of the bilge because the floor structure failed and you now have to pull the whole houseboat out of the water before it sinks because there is a 3" hole in the hull, the bilge pumps are all running max, and you...
the cover on the pump will have arrow rotation and which one is inlet/outlet based on rotation. if the crank mounted johnson pump has the inlet/outlet aimed at port, the lower one is inlet, upper is outlet. rotate the pump so the ports are aimed starboard, and the pump inlet is upper, outlet...
first, welcome aboard.
regarding your fuel tanks, remember, the bare hull had teh fuel tanks and motors installed before the hull was capped.
the choices are cut out the floor, cut out the transom, or uncap the hull.
I see you also posted on THT...
