I've always done mine with the car up on four strong axle stands. Easy to get at calipers and the job can be done in a single sequence.
Modulator bleed screws are a bit tricky to get at. I have a brake line type spanner, 6 point ring minus one side, that is a decent shape for access. Williams brand that I've had for maybe 30 years so current version may be different. No need for great torque so heating and bending the shank to adjust a spanner shape will be OK.
As its a two person job I reckon the most useful accessory is a pair of task list sheet sets with each part of the job listed in sequence and a box to be ticked when each part has been done. One sheet for each participant. Use the classic instruction, read back, execute , check off sequence.
If you've not done the job before and are trying to work off the listing in RAVE its very easy to get mixed up, loose your place, or work at cross purposes. Got my version of the sheets as a pdf on the computer "somewhere" so PM me if you think a copy may help.
Despite the number of steps involved brake bleeding on a P38 is an easy "painting by numbers" job. Unless there is an underlying fault it just works! Unlike certain lesser vehicles where brake bleeding can be equivalent to hoisting a banner invitation of the "Gremlin Party Here Today. Free Entry. Free Beer." variety.
Clive