I am deleting my flame heater right now. I can confirm that, on the intake, you need an M20 and an M18 plug. If you get hold of one of the original military ether conversion kits, these plugs are included.
Plugging the fuel supply port at the bottom of the forward-facing surface of the injection pump was a major PITA. The steering box is in the way. Removing the smaller fuel line fittings worked with a 7/16 wrench. Threading the 9/16 fitting out of the IP required a flex extension and a U-joint adapter. Getting the square drive plug in was a pain.
While I have a super cool M20-1.5 to 1/8NPT reducer bushing that came with the kit and is intended for the ether kit's thermostat, I need another one of these bushings for the kit's ether injector. The bushing would go in place of one of the intake plugs and allow mounting of the ether injector. If you have a pyro and boost gauge installed, you likely already used the 1/8 NPT port on the intake that the installation instructions ask you to use.
Alternatively, you can drill and tap the intake.
PHENIX has the bushings needed:
PHENIX-B2014-4 | PHENIX - B2014-4 - Reducer Bushing - Metric Male to NPT Female - M20 x 1.5 to 1/4 NPT - Blue - | 1
| $4.85
| $4.85
|
PHENIX-B2112 | PHENIX - B2112 - Reducer Bushing - NPT Male to NPT Female - 1/4 NPT to 1/8 NPT - Raw - | | | |