From 1982-1986 there was always at least one XC in each direction from Guildford originating from or heading to Portsmouth. These were the Mon-Sat services:
1982 and 1983: Mon-Sat one Manchester trip and v.v.
1200 from Guildford in 1982; 0900 from Guildford in 1983 (1105 and 0805 respectively from Ports Hbr). Southbound services approx 1420 from Man Picc in 1982 and approx 1320 in 1983.
1984: one northbound York (1509 from Guildford, 1413 from Ports Hbr); southbound York and Liverpool. Bizarrely the southbound York departed Guildford at 1226, at the exact same time as the Waterloo-Portsmouth stopper, though presumably the WTT time of the latter was a couple of mins later. The Liverpool would have left from Lime St at 1400-ish. Also the 0805 northbound (0900 Guildford) continued to run, formed of the southbound Liverpool from the previous night, but went to Poole via Reading - a positioning move for the 1130-ish Poole to Manchester, though it did provide connection at Reading with the "Wessex Scot".
1985: unchanged from 1984.
1986: northbound services were now to Liverpool (the 0900, or 0805 ex Ports Hbr, once again!) and Manchester (1356, I think). Southbound services were, I think, both Liverpool, one early in the morning (0700-ish from Lime St?) and the second at roughly the same time as the southbound Liverpool in 1984 and 1985.
I have the feeling the XC services from Guildford ended in 1987, not to return until Virgin days. Nonetheless loco-haulage continued to be seen at Guildford until May 1989, I think, due to the daily 50-hauled Waterloo-Portsmouth fast.
In addition to these, there was the Friday afternoon Portsmouth-Leeds, due Guildford 1346, returning Sunday evening - and a couple of summer-only Saturday services, an 1125 to Leeds being a frequent fixture, using Mk-I stock (travelled on this on 29 Sep 1984 from Guildford-Reading, in those days summer Saturdays lasted until the very end of Sep - consequently on that autumn day, I saw a procession of summer specials heading for Paignton, Newquay etc at Reading!)