Should be the same basic part as your D model YZ's
I think the last set of digits, 00 & 01 refer to colour so one may be black and the other unpainted??
Part # = 322-26281-00-00
Part Description = CAP,GRIP UPPER - Replacement Number = 322-26281-00-98 *
Model Count = 15
DT2MX 1972 250 DT2MX Dual Purpose
IT175F 1979 175 IT175 Dual-Purpose
IT250D 1977 250 IT250 Dual-Purpose
IT250E 1978 250 IT250 Dual-Purpose
IT400D 1977 400 IT400 Dual-Purpose
IT400E 1978 400 IT400 Dual-Purpose
IT400F 1979 400 IT400 Dual-Purpose
MX100A 1974 100 MX100 Off-Road
MX100B 1975 100 MX100 Off-Road
MX125A 1974 125 MX125 Off-Road
MX125B 1975 125 MX125 Off-Road
MX175A 1974 175 MX175 Off-Road
MX175B 1975 175 MX175 Off-Road
RT2MX 1972 360 RT2MX Off-Road
YZ175C 1976 175 YZ175 Competition Motocross
See also...
Part # = 431-26281-01-98
Part Description = CAP,GRIP UPPER (431-26281-01)
Model Count = 15
IT400C 1976 400 IT400 Dual-Purpose
MX250B 1975 250 MX250 Off-Road
MX400B 1975 400 MX400 Off-Road
YZ250A 1974 250 YZ250 Competition Motocross
YZ250C 1976 250 YZ250 Competition Motocross
YZ250D 1977 250 YZ250 Competition Motocross
YZ250E 1978 250 YZ250 Competition Motocross
YZ250F 1979 250 YZ250 Competition Motocross
YZ250G 1980 250 YZ250 Competition Motocross
YZ360A 1974 360 YZ360 Competition Motocross
YZ400C 1976 400 YZ400 Competition Motocross
YZ400D 1977 400 YZ400 Competition Motocross
YZ400E 1978 400 YZ400 Competition Motocross
YZ400F 1979 400 YZ400 Competition Motocross
YZ465G 1980 465 YZ465 Competition Motocross