I used "OSCCON=%01110000" in the first code, the one for the internal setup. It is not needed when using the external.

When using a 20MHz external the first config line will look like this
@ __CONFIG _CONFIG1H, _HS_OSC_1H & _FSCM_OFF_1H & _RC_OSC_1H

The HSPLL_OSC_1H is the multiplier. All this chip can do is multiply by four.

Now you will want to try over-clocking. Water cooled PICs