I think yours is May '78 and about 4500 PSN's, 3750 chassis numbers later (yours is the 253 with 63V trim? - I have a 4/78 308 Pagewood XX7 van in 1928 but it has 60V trim). The last Pagewood van PSN that I know of is 8M70LHH958052Z, a 6/78 example. Last ute is also 6/78 8N80LHH958797Z.