Tax relief on self employment earnings put into SIPP

I am about to become self-employed, and will therefore pay tax via self-assessment tax return. I will be earning around £37,000 a year, hence my top rate of tax will be the 20% basic rate. My question - is the below course of action acceptable to HMRC? I will be putting money monthly into an SIPP. This money will thus benefit from tax relief. It is my intention to pay this money in gross to the SIPP and instruct the SIPP not to obtain tax relief on it, as it has essentially been relieved at source. I will then declare this on my tax return.

Hi,
Please refer to Tax on your private pension contributions
Thank you.