Yes, just a standard LCD module, they used a 2x8 one in the original article.
The other two chips are on a seperate board, and not relevent to your design - they are a PLL and a schmitt trigger - they were used to provide a pulse output from the FGM-3 sensor used in the design.
The circuits for the project are only in one part, there is a second part, which deals with setting it up etc.
It's got connections for ICSP using the EPE TK series of programmers.
There are seven different modes:
Mode 0) Trip elapsed time and distance (km).
Mode 1) Current speed and average speed (km/h).
Mode 2) Peak speed and total difference (km/h).
Mode 3) Trip elapsed time and distance (miles).
Mode 4) Current speed and average speed (miles/h).
Mode 5) Peak speed and total difference (miles/h).
Mode 6) Current wheel rotation count, and average over ten seconds.
Mode 7) Visual warning of reset contdown on both lines.
WD1 is an audio buzzer, for audible indications. Sk1 is simply the external conenction to the board - basically power positive and negative, and a pulse input.
You would need to rewrite the entire display routines, probably using interrupts to multiplex the displays - see my tutorials for an example.
If I get time I'll scan the whole article.