The parnet cable is a DB25 male to DB25 male on the 500/2000 and female on the Amiga 1000
Looking at the pinouts on an LPT parallel cable the pinouts vary to that required for a Parnet. There is a cable diagram
that is on the Parnet disk. You have to connect (2-9) D7-D0 across along with (12) POUT, (11) BUSY and (13)SEL. Then ACK
(FLAG INTERUPT)is connected to SEL locally and (18-22) GND appears to connect to GND. Those connections vary from a
DB25 LPT parallel cable from what I can see online. Some of the labelling is different also) You would need to check.
Don't quote me. Whilst I use Parnet and have a couple of cables I bought mine ready made.
I suggest you get the Parnet disk off Aminet and check the cabling requirements from there. You would need a DB25 on
each end so first up you probably need two printer cables to hack across.
I will put an image of the Parnet document showing the cable tomorrow on my website if that helps.
UPDATE:
Here is the link to my page which includes a cable diagram from the ParNET disk and CUAmiga.
https://www.scuzzscink.com/amiga/scuzzblog_october22/scuzzblogdoctober22_2301.htm