I measured the bottom of the pump (inlet) and it was 11.25mm using a Mitutoyo 293-340-30 Digital Micrometer. The inlet on the 450 is probably the same, which is an error on my part.

Since this kit works with both the 450 and 525, I think we are good so long as the 525 is like the 450 and doesn't need the vapor ports submerged at all times.

https://walbrofuelpumps.com/walbro-t...uel-pumps.html

 

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