S12XE has two 8channel timers, TIM (port R) and ECT (port T). Also there's an 8channel PWM module (port P).
S12XE has several routing registers, which allow changing destination pins of particular peripheral modules.
MODRR allows rerouting CAN0, CAN4, SPI0, SPI1, SPI2 modules.
PTRRR allows rerouting TIM pins. Each PTRRR bit corresponds to TIM channel. PTRRRx=0 (reset default routing) makes TIMx routed to PTRx pin, PTRRRx=1 makes TIMx routed to PTPx pin.
PTLRR allows rerouting SCI4/5/6/7 modules
PTFRR allows rerouting SCI3, IIC0, and CS0/1/2/3
ECT pins are not rerouteable, only TIM pins can be routed to port P or to port R.
Table 1-8 Peripheral - Port Routing Options in S12XE reference manual doesn't include any option for ECT, only for TIM (port R / port P)
In Table 1-9 Pin-Out Summary (ECT) IOCx function is available only for port T. TIMIOCx function again is available for port R and port P.
So if you have HW done with timer pins at port P, then you need to use TIM timer.