The IP can seem intimidating the first time you do one. There are a couple simple tools I've made to make it a lot easier, but it is doable without these tools.
If you read the TM, it explains how to properly set the engine in the right position ( cyl. #1 on the compression stroke with "PC" aligned with the pointer on the flywheel ) to remove the pump,
The plunger guide is available for about $25 plus shipping.
As you may notice in my signature I rebuild both the Ambac M-50 IP and injectors for the 002 and 003, so if you're comfortable removing it you can send it to me and I'll take care of it, or if you want to try it yourself I can help talk you through it. ( Note: you need the rebuild instructions from Ambac NOT the instructions in the TM. the TM shows you how to rebuild a Bosch PSU pump, not an Ambac M-50 )
You can also send me the injectors and nozzles and I can do the injectors for you, if you'd like.
But the first step is to verify you have an Ambac pump and not a Bosch, because the Bosch does not use a replaceable plunger guide, it uses a pin through the plunger that often breaks the tip off the plunger instead of shearing the pin.
Take a look at the underside of your pump. If you see a giant flat head screw cap pointing straight down, that is a Bosch PSU.
If there is just a solid cast boss there with no screw, that is an Ambac M-50 99% of the time.
The metal tag on the side near the linkage will also tell you which pump you have.
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