exclude non receivable balances calculation in AR to GL REconciliation

I have recently started using a natural account in AR product and for enabling its Reconciliation, i changed the financial category of this account to Accounts receivables. Problem is that this account was already been used by a lot of other custom applications/manual journals due to which there is a lot of balances and Code combinations that already exists in GL. (around 10m CCID's exist)

Due to such huge balances and CCID's the performance of the program has taken a hit, and now instead of completing in seconds , its taking hours and hours to finish.

What i want is a way that i can exclude this account to be calculating the begin balance and journals for non receivables products but only calculates and reconciles the AR product data only.