Grey Tank fittings?

[ramdough]

So the tank that fits the best has no fittings.

I can use these:

1 1/2" UNISEAL Flexible Tank Adapter (Bulkhead) - 2 Pack https://a.co/d/fO0kADS

I can try to plastic weld in bungs (I have not found any hdpe bungs yet, might have to make them).
or I can put in an access cover and put in bulkheads. I wanted to avoid the access cover over fears it may leak. This is especially concerning with an off-road use, half full liquid sloshing, and in a 50” long tank.

Any suggestions?

 

[chucky]

The more i read on this maybe its ok ! worse case senario when you cut the drain hole you can put all the other screw in bungs of whatever sise as long as they fit thru the drain hole just drill your overflow vent on the topside and your inbound grey water then just take a string and a little stick and fish the internal hardware thru the big hole and pull the string out the hole your working on and dope it up and tighten good then decide how you want to attach the T handle dump valve to the big hole ! You could try a 3in uniseal and a piece of 3 in pvc pipe to glue the dump valve to the pipe ad dope the uniseal rubber and shove the 3 in in and let it dry and if it doesnt work you still have a clean hole and your pipe and valve to re use with other sealant .

 

[Third From Texas]

For "above the fill line" stuff (like the drop in, you can get away with it. But anything below surface level should be glued in place (or welded if a metal tank).

Both the grey and black tanks given to me for the build have soft seal grommet-type inputs on the upper face of the tanks.

 

[ramdough]

I am leaning towards just putting in a port hole and using threaded bulkhead fittings. At least then I know it is going to be strong.