NHS Treatment for overseas visitor. Future immigration?

Hi,
My Father has applied for ILR and we have been waiting for 6 months.
My GP advised me to register him to NHS and save the costs for private prescriptions.
Should I register him to NHS and use GP services free of charge?
Can I Use Over 60 rule to get free medicine?
Last but not the least .. Can i get him referred to a specialist doctor for his heart condition ?
After doing all or one of the above, will it impact his current application for ILR or future application for a visit visa incase of ILR turned down?

He can register with a GP but he is would not be entitled to free hospital treatment unless in an emergency. Any debt of over £1000 to the NHS could result in the refusal of his application for ILR and any future applications for entry clearance.

On what basis has he applied for ILR - according to your previous posts you are a tier1 migrant?

http://www.nhs.uk/chq/Pages/1086.aspx

Rest of my family are british citizenz... Already... My sister has applied for hij last july...i was scared to register him to GP... Coz his application was pending... I have been getting private treatment since then... But gp advised to register him... So if he writes a prescription for him.. Will that have any effect on his IlR or future visit visas... If we claim free medicines as well coz he s well over 60... This is wt GP is advising.. I am happy paying private medical costs if gp advice has any repercussion on his visa.. He dsnt knw laws regarding immigration.. Tht is why i ws here to ask u..

Many thx in anticipation..