Hi,
Actually, the datasheet (16F877), table 8-1 as well as figure 8-3 shows that the PWM generation uses TMR2, not TMR1. It DOES use the CPP1 module though but feel free to use TMR1 as you wish. You can use CPP1 for HPWM and CCP2 for capture/compare if that's what you want.

Note, this MAY be different on other PIC's but since you didn't say which one you're using a took the F877 as an example.

Hope it helps.
/Henrik Olsson.