Of all the machines i've owned, by far the easiest to work on was RFM!! Disconnect 5 or 6 plugs and the whole PF is removable (admittedly with someone helping) The fact that the PF also has 2 rails underneath means that you can sit it on a bench without any damage to the mechs, etc underneath so you can work on anything on the top. In situ in the machine it is similar to later WPC machines where the PF can be brought forward enough to provide easy access to the back and of course tipped back onto the head box to work underneath.