Although at one point the 4/6 digit did indeed point to the difference
between a 4 and a 6 cylinder engine, this was clouded by the introduction of
a turbo engine in a vehicle with the higher level of trim. Thus, a "760"
with a 4 cylinder turbo engine. Inside, the seats of a 760 from that year
should be identical to a 740, flat, broad and firm, probably the most
comfortable seat ever produced by Volvo, and far superior to the 960's from
1995 on. But they should be power adjustable in a 760.
The best way to tell the difference is from the VIN. Find a website that
explains the digits. For example, in the site listed below, they say the
fourth digit of the VIN should be F for 740 and G for 760, for the years
1981-1986. Probably true for 1988 too. There should be other sources to
check out as well:
http://www.angelfire.com/ca/TORONTO/VIN/volvocar.html
Rein Ende
Hamilton, Ontario, Canada