Via one of the numerous decoders:
P=Plymouth
M= "Medium" = Fury
41 = 4 Door Sedan
41 = 318-2bbl 8cyl 230hp
5 = Torqueflite Auto Trans
53 = 8.25"x14" WSW on steel - spare same
508 = Sch Prod Date May 8
563420 = Sales Order Number
43 = Upper Door Frame Trim-Sedan
A1 = 2.76:1 Axle ratio
TM = Trim Grade "Medium"
R5 = Vinyl Bench seats
MP = White with Turquoise (I question this one?)
PG = Paint-lower Green
PG = Paint-upper, Green
T1 = Monotone Paint
UG = Upper doors paint Green