Clark,

Excellent question. Using P2K tanks with these vents is not completely accurate. Since the type 21 tank had dome top vents, you need to look back towards the type 11/17 tank and earlier as a place to use these vents (on an AC&F tank). My current plans are to backdate the P2K type 21 tank by removing the side/top seams/rivets and adding vertical/radial courses and archer rivets to get 10,000 gallon type 11 and type 17 tanks. The F&C tank will be modified with archer rivets to make an 8K type 17. Additionally, the type 21 dome is shorter and has a larger diameter than the earlier domes so the dome area will need to be filled and new, more appropriate domes built.

Regards
Bruce

Bruce F. Smith
Auburn, AL
https://www5.vetmed.auburn.edu/~smithbf/

"Some days you are the bug, some days you are the windshield."
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